Evaluation of the Antioxidant Activity of Red Fruit (Pandanus conoideus L.) Juice Using the DPPH Radical Scavenging Assay

Abstrak

ABSTRACT: Red fruit (Pandanus conoideus Lam.), a member of the Pandanaceae family, is a traditional plant widely found in Papua, Indonesia, and has long been utilized for its nutritional and medicinal properties. Empirical evidence suggests that red fruit possesses therapeutic potential against various degenerative diseases, including cancer, cardiovascular diseases, tuberculosis, respiratory disorders, as well as certain eye and skin conditions. These health benefits are closely associated with its rich content of bioactive compounds, particularly antioxidants. This study aimed to evaluate the antioxidant activity of red fruit juice using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. The DPPH assay is a widely used method for assessing antioxidant capacity, based on the reduction of the DPPH radical, which exhibits maximum absorbance in ethanol or methanol, making it suitable for analyzing polar compounds. The antioxidant activity of red fruit juice was assessed both qualitatively and quantitatively. Qualitative analysis showed a visible color change from purple to yellow upon the addition of DPPH reagent, indicating the presence of antioxidant compounds. Quantitative analysis was performed using a UV-Visible spectrophotometer at a maximum wavelength of 519 nm, with ascorbic acid used as a standard reference. The antioxidant activity was determined by IC₅₀ (Inhibition concentration 50%) of the antioxidant compound. The results revealed that red fruit juice exhibited notable antioxidant activity, with IC₅₀ of 47.68 μg/mL. In conclusion, red fruit juice demonstrates significant antioxidant potential and may serve as a natural source of antioxidants for the prevention of oxidative stress-related diseases. These findings support the further development and utilization of P. conoideus as a functional food and natural therapeutic agent.

KEYWORDS: Absorbance; antioxidants; DPPH; red fruit; UV-Vis spectrophotometry.